A planted spillway will help drastically. I have an aq70 on a 20l with a dwarf puffer. Overkill, yes. But, it's better then the stupid 10 gallon topfin hob that was there previously. I bought mesh from ac Moore, cut to size, sandwiched moss between them, and hooked it to the spillway. It also acts as additionally bio filtration but does also hold onto mulm that can cause cloudy water after restarting the hob. Sorry, the pic is upside down.